1 1531 60 DNA METHYLATION DURING DEPLETED URANIUM-INDUCED LEUKEMIA. OBJECTIVES: THE RADIOACTIVE HEAVY METAL DEPLETED URANIUM (DU) IS USED IN KINETIC-ENERGY PENETRATORS IN MILITARY APPLICATIONS. THE OBJECTIVE OF THIS STUDY WAS TO DETERMINE INVOLVEMENT OF DNA METHYLATION IN DU-INDUCED LEUKEMIA. METHODS: METHYLATION WAS MEASURED BY DIRECT ANALYSIS OF 5-METHYLCYTOSINE CONTENT OF SPLEEN DNA IN DU LEUKEMIC MICE. RESULTS: SPLEEN HYPOMETHYLATION OCCURRED DURING DU-INDUCED LEUKEMOGENESIS (CHRONIC INTERNAL DU EXPOSURE). ABERRANT GENE TRANSCRIPTION WAS ALSO DETECTED. CONCLUSIONS: EPIGENETIC MECHANISMS ARE IMPLICATED IN DU-INDUCED LEUKEMIA. THESE DATA ARE EVIDENCE OF ABERRANT DNA HYPOMETHYLATION BEING ASSOCIATED WITH DU LEUKEMOGENESIS. 2009 2 4221 23 METHYLATION AND SILENCING OF PROTEIN TYROSINE PHOSPHATASE RECEPTOR TYPE O IN CHRONIC LYMPHOCYTIC LEUKEMIA. PURPOSE: PREVIOUS STUDIES IN OUR LABORATORY HAVE SHOWN THE PROGRESSIVE METHYLATION AND SUPPRESSION OF THE GENE ENCODING PROTEIN TYROSINE PHOSPHATASE, PTPRO, IN THE LIVERS OF RATS FED A METHYL-DEFICIENT DIET THAT INDUCES HEPATOCARCINOGENESIS. SUBSEQUENTLY, WE OBSERVED THE METHYLATION OF PTPRO IN PRIMARY HUMAN LUNG TUMORS AND ALSO SHOWED ITS POTENTIAL TUMOR SUPPRESSOR CHARACTERISTICS. THE PRESENT STUDY WAS UNDERTAKEN TO INVESTIGATE WHETHER THE TRUNCATED FORM OF PTPRO (PTPROT), SPECIFICALLY EXPRESSED IN NAIVE B LYMPHOCYTES, WAS ALSO METHYLATED AND SUPPRESSED IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), A DISEASE GENERALLY AFFECTING B LYMPHOCYTES. EXPERIMENTAL DESIGN AND RESULTS: INITIAL SCREENING SHOWED THAT 60% OF THE 52 CLL SAMPLES ANALYZED USING METHYLATION-SPECIFIC PCR ASSAY WERE METHYLATED COMPARED WITH B LYMPHOCYTES FROM NORMAL INDIVIDUALS, WHICH WERE NOT METHYLATED. THE EXPRESSION OF PTPROT, AS MEASURED BY SEMIQUANTITATIVE REVERSE TRANSCRIPTION-PCR, INVERSELY CORRELATED WITH METHYLATION IN THE FEW SAMPLES TESTED. ANALYSIS OF ADDITIONAL SAMPLES (N = 50) BY COMBINED BISULFITE RESTRICTION ANALYSIS SHOWED THAT THE PTPRO CPG ISLAND WAS METHYLATED IN 82% OF PATIENTS WITH CLL COMPARED WITH B LYMPHOCYTES FROM NORMAL INDIVIDUALS. FURTHERMORE, OVERALL EXPRESSION OF PTPRO WAS REDUCED IN CLL RELATIVE TO NORMAL LYMPHOCYTES. THE PTPRO GENE WAS ALSO SUPPRESSED BY METHYLATION IN THE CLL CELL LINE WAC3CD5, WHERE IT COULD BE REACTIVATED UPON TREATMENT WITH THE DNA HYPOMETHYLATING AGENT 5-AZAC. ECTOPIC EXPRESSION OF PTPROT IN A NONEXPRESSING CELL LINE INCREASED GROWTH INHIBITION WITH FLUDARABINE TREATMENT, A THERAPY COMMONLY USED FOR CLL. CONCLUSION: THIS STUDY REVEALS THE POTENTIAL ROLE OF PTPRO METHYLATION AND SILENCING IN CLL TUMORIGENESIS AND ALSO PROVIDES A NOVEL MOLECULAR TARGET IN THE EPIGENETIC THERAPY. 2007 3 2763 22 EXPRESSION OF THE LEUKEMIC PROGNOSTIC MARKER CD7 IS LINKED TO EPIGENETIC MODIFICATIONS IN CHRONIC MYELOID LEUKEMIA. BACKGROUND: EXPRESSION LEVELS OF THE CELL SURFACE GLYCOPROTEIN, CD7, AND THE SERINE PROTEASE, ELASTASE 2 (ELA2), IN THE LEUKEMIC CELLS OF PATIENTS WITH CHRONIC MYELOID LEUKEMIA (CML) HAVE BEEN ASSOCIATED WITH CLINICAL OUTCOME. HOWEVER, LITTLE IS KNOWN ABOUT THE MECHANISMS THAT UNDERLIE THE VARIABLE EXPRESSION OF THESE GENES IN THE LEUKEMIC CELLS. RESULTS: TO ADDRESS THIS QUESTION, WE COMPARED THE LEVEL OF THEIR EXPRESSION WITH THE DNA METHYLATION AND HISTONE ACETYLATION STATUS OF 5' SEQUENCES OF BOTH GENES IN LEUKEMIC CELL LINES AND PRIMITIVE (LIN-CD34+) LEUKEMIC CELLS FROM CHRONIC PHASE CML PATIENTS. DNA METHYLATION OF THE ELA2 GENE PROMOTER DID NOT CORRELATE WITH ITS EXPRESSION PATTERN IN LIN-CD34+ CELLS FROM CHRONIC PHASE CML PATIENT SAMPLES EVEN THOUGH THERE WAS CLEAR DIFFERENTIAL DNA METHYLATION OF THIS LOCUS IN ELA2-EXPRESSING AND NON-EXPRESSING CELL LINES. IN CONTRAST, WE FOUND A STRONG RELATION BETWEEN CD7 EXPRESSION AND TRANSCRIPTION-PERMISSIVE CHROMATIN MODIFICATIONS, BOTH AT THE LEVEL OF DNA METHYLATION AND HISTONE ACETYLATION WITH EVIDENCE OF HYPOMETHYLATION OF THE CD7 PROMOTER REGION IN THE LIN-CD34+ CELLS FROM CML PATIENTS WITH HIGH CD7 EXPRESSION. CONCLUSION: THESE FINDINGS INDICATE A LINK BETWEEN EPIGENETIC MODIFICATIONS AND CD7 EXPRESSION IN PRIMITIVE CML CELLS. 2010 4 136 21 ABERRANT DNA HYPERMETHYLATION PATTERNS LEAD TO TRANSCRIPTIONAL SILENCING OF TUMOR SUPPRESSOR GENES IN UVB-EXPOSED SKIN AND UVB-INDUCED SKIN TUMORS OF MICE. OVEREXPOSURE OF THE HUMAN SKIN TO SOLAR ULTRAVIOLET (UV) RADIATION IS THE MAJOR ETIOLOGIC FACTOR FOR DEVELOPMENT OF SKIN CANCERS. HERE, WE REPORT THE RESULTS OF EPIGENETIC MODIFICATIONS IN UV-EXPOSED SKIN AND SKIN TUMORS IN A SYSTEMATIC MANNER. THE SKIN AND TUMOR SAMPLES WERE COLLECTED AFTER CHRONIC EXPOSURE OF THE SKIN OF SKH-1 HAIRLESS MICE TO UVB RADIATION USING A WELL-ESTABLISHED PHOTOCARCINOGENESIS PROTOCOL. WE FOUND A DISTINCT DNA HYPERMETHYLATION PATTERN IN THE UVB-EXPOSED EPIDERMAL SKIN AND UVB-INDUCED SKIN TUMORS THAT WAS ASSOCIATED WITH THE ELEVATED EXPRESSION AND ACTIVITY OF THE DNA METHYLTRANSFERASES (DNMT) 1, DNMT3A AND DNMT3B. TO EXPLORE THE ROLE OF HYPERMETHYLATION IN SKIN PHOTOCARCINOGENESIS, WE FOCUSED ON THE P16(INK4A) AND RASSF1A TUMOR SUPPRESSOR GENES, WHICH ARE TRANSCRIPTIONALLY SILENCED ON METHYLATION. WE ESTABLISHED THAT THE SILENCING OF THESE GENES IN UVB-EXPOSED EPIDERMIS AND UVB-INDUCED SKIN TUMORS IS ASSOCIATED WITH A NETWORK OF EPIGENETIC MODIFICATIONS, INCLUDING HYPOACETYLATION OF HISTONE H3 AND H4 AND INCREASED HISTONE DEACETYLATION, AS WELL AS RECRUITMENT OF METHYL-BINDING PROTEINS, INCLUDING MECP2 AND MBD1, TO THE METHYLATED CPGS. HIGHER LEVELS OF DNA METHYLATION AND DNMT ACTIVITY IN HUMAN SQUAMOUS CELL CARCINOMA SPECIMENS THAN IN NORMAL HUMAN SKIN SUGGEST THAT THE DATA ARE RELEVANT CLINICALLY. OUR DATA INDICATE FOR THE FIRST TIME THAT UVB-INDUCED DNA HYPERMETHYLATION, ENHANCED DNMT ACTIVITY AND HISTONE MODIFICATIONS OCCUR IN UVB-EXPOSED SKIN AND UVB-INDUCED SKIN TUMORS AND SUGGEST THAT THESE EVENTS ARE INVOLVED IN THE SILENCING OF TUMOR SUPPRESSOR GENES AND IN SKIN TUMOR DEVELOPMENT. 2011 5 2761 22 EXPRESSION OF TESTIS-SPECIFIC GENES, TEX101 AND ODF4, IN CHRONIC MYELOID LEUKEMIA AND EVALUATION OF TEX101 IMMUNOGENICITY. BACKGROUND AND OBJECTIVES: CANCER-TESTIS (CT) ANTIGENS ARE A GROUP OF ANTIGENS WITH A RESTRICTED EXPRESSION IN NORMAL TISSUES, EXCEPT TESTIS, AND THEY HAVE ABERRANT EXPRESSION IN DIFFERENT TUMORS. THIS PATTERN OF EXPRESSION HAS MADE THEM PROMISING TARGETS FOR IMMUNOTHERAPY AND CANCER DETECTION. OUR AIM WAS TO FIND NEW MEMBERS OF THIS GROUP THAT MIGHT BE USEFUL AS MARKERS IN THE DETECTION OF CANCER AND IMMUNOTHERAPY. DESIGN AND SETTING: A DESCRIPTIVE STUDY CONDUCTED IN REFERRAL CENTERS OF TEHRAN UNIVERSITY OF MEDICAL SCIENCE FROM JANUARY 2008 TO JANUARY 2009. PATIENTS AND METHODS: WE ANALYZED THE EXPRESSION OF TWO TESTIS-SPECIFIC GENES NAMED ODF4 (OUTER DENSE FIBER OF SPERM TAILS 4) AND TEX101 (TESTIS EXPRESSED 101) IN 20 CHRONIC MYELOID LEUKEMIA (CML) AND 20 NORMAL SAMPLES BY REVERSE TRANSCRIPTION-POLYMERASE CHAIN REACTION AND SEQUENCING. IMMUNOGENICITY OF TEX101 WAS EVALUATED BY MEANS OF ENZYME-LINKED IMMUNOSORBENT ASSAY. RESULTS: THESE TWO GENES WERE EXPRESSED IN 30% OF CML PATIENTS BUT NOT IN ANY OF THE HEALTHY DONORS. HUMORAL RESPONSE AGAINST TEX101 WAS NOT DETECTED IN ANY SAMPLES. CONCLUSIONS: TEX101 AND ODF4 ARE CT GENES USEFUL FOR DETECTION OF CML. UNLIKE MANY CT GENES, OVEREXPRESSION OF TEX101 WAS NOT SHOWN TO INDUCE IMMUNOLOGIC RESPONSES IN THESE SAMPLES. ACCORDING TO THE PREVIOUS STUDIES, OVEREXPRESSION OF TEX101 LEADS TO SUPPRESSION OF CANCER INVASION AND METASTASIS; THUS, THE INDUCTION OF THE EXPRESSION OF TEX101 IN CANCER BY EPIGENETIC MECHANISMS MAY BE A TREATMENT STRATEGY. 2012 6 3125 16 GHSR DNA HYPERMETHYLATION IS A COMMON EPIGENETIC ALTERATION OF HIGH DIAGNOSTIC VALUE IN A BROAD SPECTRUM OF CANCERS. IDENTIFICATION OF A SINGLE MOLECULAR TRAIT THAT IS DETERMINANT OF COMMON MALIGNANCIES MAY SERVE AS A POWERFUL DIAGNOSTIC SUPPLEMENT TO CANCER TYPE-SPECIFIC MARKERS. HERE, WE REPORT A DNA METHYLATION MARK THAT IS CHARACTERISTIC OF SEVEN STUDIED MALIGNANCIES, NAMELY CANCERS OF LUNG, BREAST, PROSTATE, PANCREAS, COLORECTUM, GLIOBLASTOMA AND B CELL CHRONIC LYMPHOCYTIC LEUKAEMIA (CLL) (N = 137). THIS MARK WAS DEFINED BY SUBSTANTIAL HYPERMETHYLATION AT THE PROMOTER AND FIRST EXON OF GROWTH HORMONE SECRETAGOUGE RECEPTOR (GHSR) THROUGH BISULFITE PYROSEQUENCING. THE DEGREE OF ABERRANT METHYLATION WAS CAPABLE OF ACCURATE DISCRIMINATION BETWEEN CANCER AND CONTROL SAMPLES. THE HIGHEST SENSITIVITY AND SPECIFICITY OF CANCER DETECTION WAS ACHIEVED FOR CANCERS OF PANCREAS, LUNG, BREAST AND CLL YIELDING THE AREA UNDER THE CURVE (AUC) VALUES OF 1.0000, 0.9952, 0.9800 AND 0.9400, RESPECTIVELY. NARROWING TO A SINGLE CPG SITE WITHIN THE GENE'S PROMOTER OR FOUR CONSECUTIVE CPG UNITS OF THE HIGHEST METHYLATION LEVELS WITHIN THE FIRST EXON IMPROVED THE DETECTION POWER. GHSR HYPERMETHYLATION WAS DETECTED ALREADY AT THE EARLY STAGE TUMORS. THE ACCURATE PERFORMANCE OF THIS MARKER WAS FURTHER REPLICATED IN AN INDEPENDENT SET OF PANCREATIC CANCER AND CONTROL SAMPLES (N = 78). THESE FINDINGS SUPPORT THE CANDIDATURE OF GHSR METHYLATION AS A HIGHLY ACCURATE PAN-CANCER MARKER. 2015 7 145 24 ABERRANT DNA METHYLATION STATUS AND MRNA EXPRESSION LEVEL OF SMG1 GENE IN CHRONIC MYELOID LEUKEMIA: A CASE-CONTROL STUDY. OOBJECTIVE: CHRONIC MYELOID LEUKEMIA (CML) IS A MYELOPROLIFERATIVE MALIGNANCY WITH DIFFERENT STAGES. ABERRANT EPIGENETIC MODIFICATIONS, SUCH AS DNA METHYLATION, HAVE BEEN INTRODUCED AS A SIGNATURE FOR DIVERSE CANCERS WHICH ALSO PLAYS A CRUCIAL ROLE IN CML PATHOGENESIS AND DEVELOPMENT. SUPPRESSOR WITH MORPHOGENETIC EFFECT ON GENITALIA (SMG1) GENE RECENTLY HAS BEEN BROUGHT TO THE SPOTLIGHT AS A POTENT TUMOR SUPPRESSOR GENE THAT CAN BE SUPPRESSED BY TUMORS FOR FURTHER PROGRESS. THE PRESENT STUDY AIMS TO INVESTIGATE SMG1 STATUS IN CML PATIENTS. MATERIALS AND METHODS: IN THIS CASE-CONTROL STUDY, PERIPHERAL BLOOD FROM 30 PATIENTS WITH DIFFERENT PHASES OF CML [NEW CASE (N)=10, COMPLETE MOLECULAR REMISSION (CMR)=10, BLASTIC PHASE (BP)=10] AND 10 HEALTHY SUBJECTS WERE COLLECTED. METHYLATION STATUS AND EXPRESSION LEVEL OF SMG1 GENE PROMOTER WAS ASSESSED BY METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) AND QUANTITATIVE REVERSE-TRANSCRIPTION PCR, RESPECTIVELY. RESULTS: MSP RESULTS OF SMG1 GENE PROMOTOR IN THE NEW CASE GROUP WERE METHYLATED (60% METHYLATED, 30% HEMIMETHYLATED AND 10% UNMETHYLATED). ALL CMR AND CONTROL GROUP PATIENTS WERE UNMETHYLATED IN THE SMG1 GENE PROMOTER. IN THE BP GROUP, METHYLATED SMG1 PROMOTER WAS SEEN (50% OF PATIENTS HAD A METHYLATED STATUS AND 50% HAD HEMIMETHYLATED STATUS). IN COMPARISON WITH THE HEALTHY SUBJECTS, EXPRESSION LEVEL OF SMG1 IN THE NEW CASE GROUP WAS DECREASED (P<0.01); IN THE CMR GROUP AND BP-CML GROUPS, IT WAS INCREASED (P<0.05). NO SIGNIFICANT CORRELATION BETWEEN PATIENTS' HEMATOLOGICAL FEATURES AND SMG1 METHYLATION WAS SEEN. CONCLUSION: OUR RESULTS DEMONSTRATED THAT ABERRANT METHYLATION OF SMG1 OCCURRED IN CML PATIENTS AND IT HAD A SIGNIFICANT ASSOCIATION WITH SMG1 EXPRESSION. SMG1 GENE PROMOTER SHOWED DIVERSE METHYLATED STATUS AND SUBSEQUENT EXPRESSION LEVELS IN DIFFERENT PHASES OF CML. THESE FINDINGS SUGGESTED POSSIBLE PARTICIPATION OF SMG1 SUPPRESSION IN THE CML PATHOGENESIS. 2022 8 493 19 ASSESSMENT OF P53 AND ATM FUNCTIONALITY IN CHRONIC LYMPHOCYTIC LEUKEMIA BY MULTIPLEX LIGATION-DEPENDENT PROBE AMPLIFICATION. THE ATM-P53 DNA-DAMAGE RESPONSE (DDR) PATHWAY HAS A CRUCIAL ROLE IN CHEMORESISTANCE IN CLL, AS INDICATED BY THE ADVERSE PROGNOSTIC IMPACT OF GENETIC ABERRATIONS OF TP53 AND ATM. IDENTIFYING AND DISTINGUISHING TP53 AND ATM FUNCTIONAL DEFECTS HAS BECOME RELEVANT AS EPIGENETIC AND POSTTRANSCRIPTIONAL DYSREGULATION OF THE ATM/P53 AXIS IS INCREASINGLY BEING RECOGNIZED AS THE UNDERLYING CAUSE OF CHEMORESISTANCE. ALSO, SPECIFIC TREATMENTS SENSITIZING TP53- OR ATM-DEFICIENT CLL CELLS ARE EMERGING. WE THEREFORE DEVELOPED A NEW ATM-P53 FUNCTIONAL ASSAY WITH THE AIM TO (I) IDENTIFY AND (II) DISTINGUISH ABNORMALITIES OF TP53 VERSUS ATM AND (III) ENABLE THE IDENTIFICATION OF ADDITIONAL DEFECTS IN THE ATM-P53 PATHWAY. REVERSED TRANSCRIPTASE MULTIPLEX LIGATION-DEPENDENT PROBE AMPLIFICATION (RT-MLPA) WAS USED TO MEASURE ATM AND/OR P53-DEPENDENT GENES AT THE RNA LEVEL FOLLOWING DNA DAMAGE USING IRRADIATION. HERE, WE SHOWED THAT THIS ASSAY IS ABLE TO IDENTIFY AND DISTINGUISH THREE SUBGROUPS OF CLL TUMORS (I.E., TP53-DEFECTIVE, ATM-DEFECTIVE AND WT) AND IS ALSO ABLE TO DETECT ADDITIONAL SAMPLES WITH A DEFECTIVE DDR, WITHOUT MOLECULAR ABERRATIONS IN TP53 AND/OR ATM. THESE FINDINGS MAKE THE ATM-P53 RT-MLPA FUNCTIONAL ASSAY A PROMISING PROGNOSTIC TOOL FOR PREDICTING TREATMENT RESPONSES IN CLL. 2015 9 3468 32 HYPOXIA-INDUCED DNA HYPERMETHYLATION IN HUMAN PULMONARY FIBROBLASTS IS ASSOCIATED WITH THY-1 PROMOTER METHYLATION AND THE DEVELOPMENT OF A PRO-FIBROTIC PHENOTYPE. BACKGROUND: PULMONARY FIBROSIS IS A DEBILITATING AND LETHAL DISEASE WITH NO EFFECTIVE TREATMENT OPTIONS. UNDERSTANDING THE PATHOLOGICAL PROCESSES AT PLAY WILL DIRECT THE APPLICATION OF NOVEL THERAPEUTIC AVENUES. HYPOXIA HAS BEEN IMPLICATED IN THE PATHOGENESIS OF PULMONARY FIBROSIS YET THE PRECISE MECHANISM BY WHICH IT CONTRIBUTES TO DISEASE PROGRESSION REMAINS TO BE FULLY ELUCIDATED. IT HAS BEEN SHOWN THAT CHRONIC HYPOXIA CAN ALTER DNA METHYLATION PATTERNS IN TUMOUR-DERIVED CELL LINES. THIS EPIGENETIC ALTERATION CAN INDUCE CHANGES IN CELLULAR PHENOTYPE WITH PROMOTER METHYLATION BEING ASSOCIATED WITH GENE SILENCING. OF PARTICULAR RELEVANCE TO IDIOPATHIC PULMONARY FIBROSIS (IPF) IS THE OBSERVATION THAT THY-1 PROMOTER METHYLATION IS ASSOCIATED WITH A MYOFIBROBLAST PHENOTYPE WHERE LOSS OF THY-1 OCCURS ALONGSIDE INCREASED ALPHA SMOOTH MUSCLE ACTIN (ALPHA-SMA) EXPRESSION. THE INITIAL AIM OF THIS STUDY WAS TO DETERMINE WHETHER HYPOXIA REGULATES DNA METHYLATION IN NORMAL HUMAN LUNG FIBROBLASTS (CCD19LU). AS IT HAS BEEN REPORTED THAT HYPOXIA SUPPRESSES THY-1 EXPRESSION DURING LUNG DEVELOPMENT WE ALSO STUDIED THE EFFECT OF HYPOXIA ON THY-1 PROMOTER METHYLATION AND GENE EXPRESSION. METHODS: CCD19LU WERE GROWN FOR UP TO 8 DAYS IN HYPOXIA AND ASSESSED FOR GLOBAL CHANGES IN DNA METHYLATION USING FLOW CYTOMETRY. REAL-TIME PCR WAS USED TO QUANTIFY EXPRESSION OF THY-1, ALPHA-SMA, COLLAGEN I AND III. GENOMIC DNA WAS BISULPHITE TREATED AND METHYLATION SPECIFIC PCR (MSPCR) WAS USED TO EXAMINE THE METHYLATION STATUS OF THE THY-1 PROMOTER. RESULTS: SIGNIFICANT GLOBAL HYPERMETHYLATION WAS DETECTED IN HYPOXIC FIBROBLASTS RELATIVE TO NORMOXIC CONTROLS AND WAS ACCOMPANIED BY INCREASED EXPRESSION OF MYOFIBROBLAST MARKERS. THY-1 MRNA EXPRESSION WAS SUPPRESSED IN HYPOXIC CELLS, WHICH WAS RESTORED WITH THE DEMETHYLATING AGENT 5-AZA-2'-DEOXYCYTIDINE. MSPCR REVEALED THAT THY-1 BECAME METHYLATED FOLLOWING FIBROBLAST EXPOSURE TO 1% O2. CONCLUSION: THESE DATA SUGGEST THAT GLOBAL AND GENE-SPECIFIC CHANGES IN DNA METHYLATION MAY PLAY AN IMPORTANT ROLE IN FIBROBLAST FUNCTION IN HYPOXIA. 2012 10 1325 20 DEPLETED URANIUM INDUCES SEX- AND TISSUE-SPECIFIC METHYLATION PATTERNS IN ADULT ZEBRAFISH. WE EXAMINED THE EFFECTS OF CHRONIC EXPOSURE TO DIFFERENT CONCENTRATIONS (2 AND 20 MUG L(-)(1)) OF ENVIRONMENTALLY RELEVANT WATERBORNE DEPLETED URANIUM (DU) ON THE DNA METHYLATION PATTERNS BOTH AT HPAII RESTRICTION SITES (5'-CCGG-3') AND ACROSS THE WHOLE GENOME IN THE ZEBRAFISH BRAIN, GONADS, AND EYES. WE FIRST IDENTIFIED SEX-DEPENDENT DIFFERENCES IN THE METHYLATION LEVEL OF HPAII SITES AFTER EXPOSURE. IN MALES, THESE EFFECTS WERE PRESENT AS EARLY AS 7 DAYS AFTER EXPOSURE TO 20 MUG L(-)(1) DU, AND WERE EVEN MORE PRONOUNCED IN THE BRAIN, GONADS, AND EYES AFTER 24 DAYS. HOWEVER, IN FEMALES, HYPOMETHYLATION WAS ONLY OBSERVED IN THE GONADS AFTER EXPOSURE TO 20 MUG L(-)(1) DU FOR 24 DAYS. SEX-SPECIFIC EFFECTS OF DU WERE ALSO APPARENT AT THE WHOLE-GENOME LEVEL, BECAUSE IN MALES, EXPOSURE TO 20 MUG L(-)(1) DU FOR 24 DAYS RESULTED IN CYTOSINE HYPERMETHYLATION IN THE BRAIN AND EYES AND HYPOMETHYLATION IN THE GONADS. IN CONTRAST, IN FEMALES, HYPERMETHYLATION WAS OBSERVED IN THE BRAIN AFTER EXPOSURE TO BOTH CONCENTRATIONS OF DU FOR 7 DAYS. BASED ON OUR CURRENT KNOWLEDGE OF URANIUM TOXICITY, SEVERAL HYPOTHESES ARE PROPOSED TO EXPLAIN THESE FINDINGS, INCLUDING THE INVOLVEMENT OF OXIDATIVE STRESS, ALTERATION OF DEMETHYLATION ENZYMES AND THE CALCIUM SIGNALING PATHWAY. THIS STUDY REPORTS, FOR THE FIRST TIME, THE SEX- AND TISSUE-SPECIFIC EPIGENETIC CHANGES THAT OCCUR IN A NONHUMAN ORGANISM AFTER EXPOSURE TO ENVIRONMENTALLY RELEVANT CONCENTRATIONS OF URANIUM, WHICH COULD INDUCE TRANSGENERATIONAL EPIGENETIC EFFECTS. 2016 11 494 19 ASSESSMENT OF PROMOTER METHYLATION IDENTIFIES PTCH AS A PUTATIVE TUMOR-SUPPRESSOR GENE IN HUMAN CLL. BACKGROUND: CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS CHARACTERIZED BY A CLONAL ACCUMULATION OF NEOPLASTIC LYMPHOCYTES, INDICATING DISRUPTION OF APOPTOSIS. PATIENTS AND METHODS: DIFFERENTIAL METHYLATION HYBRIDIZATION ANALYSIS WAS PERFORMED TO IDENTIFY NOVEL TARGET GENES SILENCED BY CPG ISLAND METHYLATION IN PATIENTS WITH CLL. RESULTS: PATCHED (PTCH), A TUMOR-SUPPRESSOR GENE, WAS FOUND TO BE FREQUENTLY METHYLATED IN CLL SAMPLES COMPARED TO SAMPLES DERIVED FROM HEALTHY INDIVIDUALS. DE NOVO METHYLATION OF A CPG ISLAND REGION LOCATED UPSTREAM OF PTCH EXON 1 WAS CONFIRMED BY PYROSEQUENCING IN 17/37 (46%) OF PERIPHERAL BLOOD MONONUCLEAR CELLS OF PATIENTS WITH CLL, BUT IN NONE ISOLATED FROM SEVEN HEALTHY INDIVIDUALS. NO ASSOCIATION WAS FOUND BETWEEN PTCH HYPERMETHYLATION AND CURRENTLY USED PROGNOSTIC CLL FACTORS. CONCLUSION: OUR INVESTIGATION SUGGESTS THAT EPIGENETIC SILENCING OF PTCH IS A MECHANISM CONTRIBUTING TO CLL TUMORIGENESIS. 2016 12 3049 18 GENOME-WIDE ANALYSIS REVEALS ZINC TRANSPORTER ZIP9 REGULATED BY DNA METHYLATION PROMOTES RADIATION-INDUCED SKIN FIBROSIS VIA THE TGF-BETA SIGNALING PATHWAY. RADIATION-INDUCED SKIN FIBROSIS IS A DETRIMENTAL AND CHRONIC DISORDER THAT OCCURS AFTER RADIATION EXPOSURE. DNA METHYLATION HAS BEEN CHARACTERIZED AS AN IMPORTANT REGULATORY MECHANISM OF MULTIPLE PATHOLOGICAL PROCESSES. IN THIS STUDY, WE COMPARED THE GENOME-WIDE DNA METHYLATION STATUS IN RADIATION-INDUCED FIBROTIC SKIN AND ADJACENT NORMAL TISSUES OF RATS BY METHYLATED DNA IMMUNOPRECIPITATION SEQUENCING. RADIATION-INDUCED FIBROTIC SKIN SHOWED DIFFERENTIALLY METHYLATED REGIONS ASSOCIATED WITH 3,650 PROTEIN-CODING GENES, 72 MICRORNAS, 5,836 LONG NONCODING RNAS AND 3 PIWI-INTERACTING RNAS. BY INTEGRATING THE MRNA AND METHYLATION PROFILES, THE ZINC TRANSPORTER SLC39A9/ZIP9 WAS INVESTIGATED IN GREATER DETAIL. THE PROTEIN LEVEL OF ZIP9 WAS INCREASED IN IRRADIATED SKIN TISSUES OF HUMANS, MONKEYS, AND RATS, ESPECIALLY IN RADIOGENIC FIBROTIC SKIN TISSUES. RADIATION INDUCED THE DEMETHYLATION OF A CPG DINUCLEOTIDE IN EXON 1 OF ZIP9 THAT RESULTED IN RECRUITMENT OF THE TRANSCRIPTIONAL FACTOR SP1 AND INCREASED ZIP9 EXPRESSION. OVEREXPRESSION OF ZIP9 RESULTED IN ACTIVATION OF THE PROFIBROTIC TRANSFORMING GROWTH FACTOR-BETA SIGNALING PATHWAY THROUGH PROTEIN KINASE B IN HUMAN FIBROBLASTS. IN ADDITION, RADIATION-INDUCED SKIN FIBROSIS WAS ASSOCIATED WITH INCREASED ZINC ACCUMULATION. THE ZINC CHELATOR N,N,N',N'-TETRAKIS(2-PYRIDYLMETHYL)-1,2-ETHYLENEDIAMINE ABROGATED ZIP9-INDUCED ACTIVATION OF THE TRANSFORMING GROWTH FACTOR-BETA SIGNALING PATHWAY AND ATTENUATED RADIATION-INDUCED SKIN FIBROSIS IN A RAT MODEL. IN SUMMARY, OUR FINDINGS ILLUSTRATE EPIGENETIC REGULATION OF ZIP9 AND ITS CRITICAL ROLE IN PROMOTING RADIATION-INDUCED SKIN FIBROSIS. 2020 13 155 22 ABERRANT METHYLATION OF POLO-LIKE KINASE CPG ISLANDS IN PLK4 HETEROZYGOUS MICE. BACKGROUND: HEPATOCELLULAR CARCINOMA (HCC), ONE OF THE MOST COMMON CANCERS WORLD-WIDE OCCURS TWICE AS OFTEN IN MEN COMPARED TO WOMEN. PREDISPOSING CONDITIONS SUCH AS ALCOHOLISM, CHRONIC VIRAL HEPATITIS, AFLATOXIN B1 INGESTION, AND CIRRHOSIS ALL CONTRIBUTE TO THE DEVELOPMENT OF HCC. METHODS: WE USED A COMBINATION OF METHYLATION SPECIFIC PCR AND BISULFITE SEQUENCING, QREAL-TIME PCR (QPCR), AND WESTERN BLOT ANALYSIS TO EXAMINE EPIGENETIC CHANGES FOR THE POLO-LIKE KINASES (PLKS) DURING THE DEVELOPMENT OF HEPATOCELLULAR CARCINOMA (HCC) IN PLK4 HETEROZYGOUS MICE AND MURINE EMBRYONIC FIBROBLASTS (MEFS). RESULTS: HERE WE REPORT THAT THE PROMOTER METHYLATION OF PLK4 CPG ISLANDS INCREASES WITH AGE, WAS MORE PREVALENT IN MALES AND THAT PLK4 EPIGENETIC MODIFICATION AND SUBSEQUENT DOWNREGULATION OF EXPRESSION WAS ASSOCIATED WITH THE DEVELOPMENT OF HCC IN PLK4 MUTANT MICE. INTERESTINGLY, THE OPPOSITE OCCURS WITH ANOTHER PLK FAMILY MEMBER, PLK1 WHICH WAS TYPICALLY HYPERMETHYLATED IN NORMAL LIVER TISSUE BUT BECAME HYPOMETHYLATED AND UPREGULATED IN LIVER TUMOURS. FURTHERMORE, UPON ALCOHOL EXPOSURE MURINE EMBRYONIC FIBROBLASTS EXHIBITED INCREASED PLK4 HYPERMETHYLATION AND DOWNREGULATION ALONG WITH INCREASED CENTROSOME NUMBERS AND MULTINUCLEATION. CONCLUSIONS: THESE RESULTS SUGGEST THAT ABERRANT PLK METHYLATION IS CORRELATED WITH THE DEVELOPMENT OF HCC IN MICE. 2011 14 546 23 ATTENUATED EXPRESSION OF SLCO2A1 CAUSED BY DNA METHYLATION IN PEDIATRIC INFLAMMATORY BOWEL DISEASE. BACKGROUND: SLCO2A1 ENCODES A PROSTAGLANDIN (PG) TRANSPORTER, AND AUTOSOMAL RECESSIVE PATHOGENIC VARIANTS OF THIS GENE CAUSE CHRONIC ENTEROPATHY ASSOCIATED WITH SLCO2A1. IT IS UNCLEAR WHETHER A HETEROZYGOUS PATHOGENIC VARIANT OF SLCO2A1 HAS A ROLE IN THE PATHOGENESIS OF OTHER TYPES OF INFLAMMATORY BOWEL DISEASE (IBD). IN THIS STUDY, WE INVESTIGATED THE POSSIBLE INVOLVEMENT OF A LOCAL EPIGENETIC ALTERATION IN SLCO2A1 IN PATIENTS WITH A HETEROZYGOUS PATHOGENIC VARIANT. METHODS: WE CONDUCTED WHOLE-EXOME SEQUENCING OF SAMPLES FROM 2 SISTERS WITH SUSPECTED MONOGENIC IBD. IN ADDITION, WE PERFORMED BISULFITE SEQUENCING USING DNA EXTRACTED FROM THEIR SMALL AND LARGE INTESTINE SAMPLES TO EXPLORE EPIGENETIC ALTERATIONS. RESULTS: A HETEROZYGOUS SPLICING SITE VARIANT, SLCO2A1:C.940 + 1G > A, WAS DETECTED IN BOTH PATIENTS. TO EXPLORE THE POSSIBLE INVOLVEMENT OF EPIGENETIC ALTERATIONS, WE ANALYZED PROTEIN AND MESSENGER RNA EXPRESSION OF SLCO2A1, AND OBSERVED ATTENUATED SLCO2A1 EXPRESSION IN THE INFLAMED LESIONS OF THESE PATIENTS COMPARED WITH THAT IN THE CONTROL INDIVIDUALS. FURTHERMORE, BISULFITE SEQUENCING INDICATED DENSE METHYLATION IN THE PROMOTER REGION OF SLCO2A1 ONLY IN THE INFLAMED LESIONS OF BOTH PATIENTS. THE URINARY PG METABOLITE LEVELS IN THESE PATIENTS WERE COMPARABLE TO THOSE IN PATIENTS WITH CHRONIC ENTEROPATHY ASSOCIATED WITH SLCO2A1 AND HIGHER THAN THOSE IN THE CONTROL INDIVIDUALS. WE FOUND CONSIDERABLY HIGHER LEVELS OF THE METABOLITES IN PATIENT 1, WHO SHOWED MORE SEVERE SYMPTOMS THAN PATIENT 2. CONCLUSIONS: LOCAL DNA METHYLATION ATTENUATED SLCO2A1 EXPRESSION, WHICH MAY EVOKE LOCAL INFLAMMATION OF THE MUCOSA BY THE UNINCORPORATED PG. THESE FINDINGS MAY IMPROVE OUR UNDERSTANDING OF THE EPIGENETIC MECHANISMS UNDERLYING IBD DEVELOPMENT. 2023 15 4694 18 NEXT-GENERATION SEQUENCING IDENTIFIES MAJOR DNA METHYLATION CHANGES DURING PROGRESSION OF PH+ CHRONIC MYELOID LEUKEMIA. LITTLE IS KNOWN ABOUT THE IMPACT OF DNA METHYLATION ON THE EVOLUTION/PROGRESSION OF PH+ CHRONIC MYELOID LEUKEMIA (CML). WE INVESTIGATED THE METHYLOME OF CML PATIENTS IN CHRONIC PHASE (CP-CML), ACCELERATED PHASE (AP-CML) AND BLAST CRISIS (BC-CML) AS WELL AS IN CONTROLS BY REDUCED REPRESENTATION BISULFITE SEQUENCING. ALTHOUGH ONLY ~600 DIFFERENTIALLY METHYLATED CPG SITES WERE IDENTIFIED IN SAMPLES OBTAINED FROM CP-CML PATIENTS COMPARED WITH CONTROLS, ~6500 DIFFERENTIALLY METHYLATED CPG SITES WERE FOUND IN SAMPLES FROM BC-CML PATIENTS. IN THE MAJORITY OF AFFECTED CPG SITES, METHYLATION WAS INCREASED. IN CP-CML PATIENTS WHO PROGRESSED TO AP-CML/BC-CML, WE IDENTIFIED UP TO 897 GENES THAT WERE METHYLATED AT THE TIME OF PROGRESSION BUT NOT AT THE TIME OF DIAGNOSIS. USING RNA-SEQUENCING, WE OBSERVED DOWNREGULATED EXPRESSION OF MANY OF THESE GENES IN BC-CML COMPARED WITH CP-CML SAMPLES. SEVERAL OF THEM ARE WELL-KNOWN TUMOR-SUPPRESSOR GENES OR REGULATORS OF CELL PROLIFERATION, AND GENE RE-EXPRESSION WAS OBSERVED BY THE USE OF EPIGENETIC ACTIVE DRUGS. TOGETHER, OUR RESULTS DEMONSTRATE THAT CPG SITE METHYLATION CLEARLY INCREASES DURING CML PROGRESSION AND THAT IT MAY PROVIDE A USEFUL BASIS FOR REVEALING NEW TARGETS OF THERAPY IN ADVANCED CML. 2016 16 1334 21 DEREGULATION OF AIOLOS EXPRESSION IN CHRONIC LYMPHOCYTIC LEUKEMIA IS ASSOCIATED WITH EPIGENETIC MODIFICATIONS. CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS CHARACTERIZED BY A CLONAL ACCUMULATION OF MATURE NEOPLASTIC B CELLS THAT ARE RESISTANT TO APOPTOSIS. AIOLOS, A MEMBER OF THE IKAROS FAMILY OF ZINC-FINGER TRANSCRIPTION FACTORS, PLAYS AN IMPORTANT ROLE IN THE CONTROL OF MATURE B LYMPHOCYTE DIFFERENTIATION AND MATURATION. IN THIS STUDY, WE SHOWED THAT AIOLOS EXPRESSION IS UP-REGULATED IN B-CLL CELLS. THIS OVEREXPRESSION DOES NOT IMPLICATE ISOFORM IMBALANCE OR DISTURB AIOLOS SUBCELLULAR LOCALIZATION. THE CHROMATIN STATUS AT THE AIOLOS PROMOTER IN CLL IS DEFINED BY THE DEMETHYLATION OF DNA AND AN ENRICHMENT OF EUCHROMATIN ASSOCIATED HISTONE MARKERS, SUCH AS THE DIMETHYLATION OF THE LYSINE 4 ON HISTONE H3. THESE EPIGENETIC MODIFICATIONS SHOULD ALLOW ITS UPSTREAM EFFECTORS, SUCH AS NUCLEAR FACTOR-KAPPAB, CONSTITUTIVELY ACTIVATED IN CLL, TO GAIN ACCESS TO PROMOTER, RESULTING UP-REGULATION OF AIOLOS. TO DETERMINE THE CONSEQUENCES OF AIOLOS DEREGULATION IN CLL, WE ANALYZED THE EFFECTS OF AIOLOS OVEREXPRESSION OR DOWN-REGULATION ON APOPTOSIS. AIOLOS IS INVOLVED IN CELL SURVIVAL BY REGULATING THE EXPRESSION OF SOME BCL-2 FAMILY MEMBERS. OUR RESULTS STRONGLY SUGGEST THAT AIOLOS DEREGULATION BY EPIGENETIC MODIFICATIONS MAY BE A HALLMARK OF CLL. 2011 17 11 24 15Q12 VARIANTS, SPUTUM GENE PROMOTER HYPERMETHYLATION, AND LUNG CANCER RISK: A GWAS IN SMOKERS. BACKGROUND: LUNG CANCER IS THE LEADING CAUSE OF CANCER-RELATED MORTALITY WORLDWIDE. DETECTION OF PROMOTER HYPERMETHYLATION OF TUMOR SUPPRESSOR GENES IN EXFOLIATED CELLS FROM THE LUNG PROVIDES AN ASSESSMENT OF FIELD CANCERIZATION THAT IN TURN PREDICTS LUNG CANCER. THE IDENTIFICATION OF GENETIC DETERMINANTS FOR THIS VALIDATED CANCER BIOMARKER SHOULD PROVIDE NOVEL INSIGHTS INTO MECHANISMS UNDERLYING EPIGENETIC REPROGRAMMING DURING LUNG CARCINOGENESIS. METHODS: A GENOME-WIDE ASSOCIATION STUDY USING GENERALIZED ESTIMATING EQUATIONS AND LOGISTIC REGRESSION MODELS WAS CONDUCTED IN TWO GEOGRAPHICALLY INDEPENDENT SMOKER COHORTS TO IDENTIFY LOCI AFFECTING THE PROPENSITY FOR CANCER-RELATED GENE METHYLATION THAT WAS ASSESSED BY A 12-GENE PANEL INTERROGATED IN SPUTUM. ALL STATISTICAL TESTS WERE TWO-SIDED. RESULTS: TWO SINGLE NUCLEOTIDE POLYMORPHISMS (SNPS) AT 15Q12 (RS73371737 AND RS7179575) THAT DROVE GENE METHYLATION WERE DISCOVERED AND REPLICATED WITH RS73371737 REACHING GENOME-WIDE SIGNIFICANCE (P = 3.3X10(-8)). A HAPLOTYPE CARRYING RISK ALLELES FROM THE TWO 15Q12 SNPS CONFERRED 57% INCREASED RISK FOR GENE METHYLATION (P = 2.5X10(-9)). RS73371737 REDUCED GABRB3 EXPRESSION IN LUNG CELLS AND INCREASED RISK FOR SMOKING-INDUCED CHRONIC MUCOUS HYPERSECRETION. FURTHERMORE, SUBJECTS WITH VARIANT HOMOZYGOTE OF RS73371737 HAD A TWO-FOLD INCREASE IN RISK FOR LUNG CANCER (P = .0043). PATHWAY ANALYSIS IDENTIFIED DNA DOUBLE-STRAND BREAK REPAIR BY HOMOLOGOUS RECOMBINATION (DSBR-HR) AS A MAJOR PATHWAY AFFECTING SUSCEPTIBILITY FOR GENE METHYLATION THAT WAS VALIDATED BY MEASURING CHROMATID BREAKS IN LYMPHOCYTES CHALLENGED BY BLEOMYCIN. CONCLUSIONS: A FUNCTIONAL 15Q12 VARIANT WAS IDENTIFIED AS A RISK FACTOR FOR GENE METHYLATION AND LUNG CANCER. THE ASSOCIATIONS COULD BE MEDIATED BY GABAERGIC SIGNALING THAT DRIVES THE SMOKING-INDUCED MUCOUS CELL METAPLASIA. OUR FINDINGS ALSO SUBSTANTIATE DSBR-HR AS A CRITICAL PATHWAY DRIVING EPIGENETIC GENE SILENCING. 2015 18 4516 17 MULTI-OMICS CHARACTERIZATION OF INFLAMMATORY BOWEL DISEASE-INDUCED HYPERPLASIA/DYSPLASIA IN THE RAG2(-/-)/IL10(-/-) MOUSE MODEL. EPIGENETIC DYSREGULATION IS HYPOTHESIZED TO PLAY A ROLE IN THE OBSERVED ASSOCIATION BETWEEN INFLAMMATORY BOWEL DISEASE (IBD) AND COLON TUMOR DEVELOPMENT. IN THE PRESENT WORK, DNA METHYLOME, HYDROXYMETHYLOME, AND TRANSCRIPTOME ANALYSES WERE CONDUCTED IN PROXIMAL COLON TISSUES HARVESTED FROM THE HELICOBACTER HEPATICUS (H. HEPATICUS)-INFECTED MURINE MODEL OF IBD. REDUCED REPRESENTATION BISULFITE SEQUENCING (RRBS) AND OXIDATIVE RRBS (OXRRBS) ANALYSES IDENTIFIED 1606 DIFFERENTIALLY METHYLATED REGIONS (DMR) AND 3011 DIFFERENTIALLY HYDROXYMETHYLATED REGIONS (DHMR). THESE DMR/DHMR OVERLAPPED WITH GENES THAT ARE ASSOCIATED WITH GASTROINTESTINAL DISEASE, INFLAMMATORY DISEASE, AND CANCER. RNA-SEQ REVEALED PRONOUNCED EXPRESSION CHANGES OF A NUMBER OF GENES ASSOCIATED WITH INFLAMMATION AND CANCER. SEVERAL GENES INCLUDING DUOX2, TGM2, CDHR5, AND HK2 EXHIBITED CHANGES IN BOTH DNA METHYLATION/HYDROXYMETHYLATION AND GENE EXPRESSION LEVELS. OVERALL, OUR RESULTS SUGGEST THAT CHRONIC INFLAMMATION TRIGGERS CHANGES IN METHYLATION AND HYDROXYMETHYLATION PATTERNS IN THE GENOME, ALTERING THE EXPRESSION OF KEY TUMORIGENESIS GENES AND POTENTIALLY CONTRIBUTING TO THE INITIATION OF COLORECTAL CANCER. 2020 19 2327 23 EPIGENETIC REGULATION OF HUMAN CANCER/TESTIS ANTIGEN GENE, HAGE, IN CHRONIC MYELOID LEUKEMIA. BACKGROUND AND OBJECTIVES: CANCER TESTIS ANTIGENS (CTA) PROVIDE ATTRACTIVE TARGETS FOR CANCER-SPECIFIC IMMUNOTHERAPY. ALTHOUGH CTA GENES ARE EXPRESSED IN SOME NORMAL TISSUES, SUCH AS THE TESTIS, THIS IMMUNOLOGICALLY PROTECTED SITE LACKS MHC I EXPRESSION AND AS SUCH, DOES NOT PRESENT SELF ANTIGENS TO T CELLS. TO DATE, CTA GENES HAVE BEEN SHOWN TO BE EXPRESSED IN A RANGE OF SOLID TUMORS VIA DEMETHYLATION OF THEIR PROMOTER CPG ISLANDS, BUT RARELY IN CHRONIC MYELOID LEUKEMIA (CML) OR OTHER HEMATOLOGIC MALIGNANCIES. DESIGN AND METHODS: IN THIS STUDY, THE METHYLATION STATUS OF THE HAGE CTA GENE PROMOTER WAS ANALYZED BY QUANTITATIVE METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) AND SEQUENCING IN FOUR PHILADELPHIA-POSITIVE CELL LINES (TCC-S, K562, KU812 AND KYO-1) AND IN CML SAMPLES TAKEN FROM PATIENTS IN CHRONIC PHASE (CP N=215) OR BLAST CRISIS (BC N=47). HAGE EXPRESSION WAS ASSESSED BY QUANTITATIVE REVERSE TRANSCRIPTASE-POLYMERASE CHAIN REACTION. RESULTS: THE TCC-S CELL LINE SHOWED DEMETHYLATION OF HAGE THAT WAS ASSOCIATED WITH OVER-EXPRESSION OF THIS GENE. HAGE HYPOMETHYLATION WAS SIGNIFICANTLY MORE FREQUENT IN BC (46%) THAN IN CP (22%) (P=0.01) AND WAS CORRELATED WITH HIGH EXPRESSION LEVELS OF HAGE TRANSCRIPTS (P<0.0001). OF NOTE, IN CP-CML, EXTENSIVE HAGE HYPOMETHYLATION WAS ASSOCIATED WITH POORER PROGNOSIS IN TERMS OF CYTOGENETIC RESPONSE TO INTERFERON (P=0.01) OR IMATINIB (P=0.01), MOLECULAR RESPONSE TO IMATINIB (P=0.003) AND PROGRESSION-FREE SURVIVAL (P=0.05). INTERPRETATIONS AND CONCLUSION: THE METHYLATION STATUS OF THE HAGE PROMOTER DIRECTLY CORRELATES WITH ITS EXPRESSION IN BOTH CML CELL LINES AND PATIENTS AND IS ASSOCIATED WITH ADVANCED DISEASE AND POOR OUTCOME. 2007 20 1846 16 EFFECTS OF TWO TYPES OF ENERGY RESTRICTION ON METHYLATION LEVELS OF ADIPONECTIN RECEPTOR 1 AND LEPTIN RECEPTOR OVERLAPPING TRANSCRIPT IN A MOUSE MAMMARY TUMOUR VIRUS-TRANSFORMING GROWTH FACTOR-ALPHA BREAST CANCER MOUSE MODEL. THE ROLE OF ADIPONECTIN AND LEPTIN SIGNALLING PATHWAYS HAS BEEN SUGGESTED TO PLAY IMPORTANT ROLES IN THE PROTECTIVE EFFECTS OF ENERGY RESTRICTION (ER) ON MAMMARY TUMOUR (MT) DEVELOPMENT. TO STUDY THE EFFECTS OF ER ON THE METHYLATION LEVELS IN ADIPONECTIN RECEPTOR 1 (ADIPOR1) AND LEPTIN RECEPTOR OVERLAPPING TRANSCRIPT (LEPROT) GENES USING THE PYROSEQUENCING METHOD IN MAMMARY FAT PAD TISSUE, MOUSE MAMMARY TUMOUR VIRUS-TRANSFORMING GROWTH FACTOR-ALPHA (MMTV-TGF-ALPHA) FEMALE MICE WERE RANDOMLY ASSIGNED TO AD LIBITUM (AL), CHRONIC ER (CER, 15 % ER) OR INTERMITTENT ER (3 WEEKS AL AND 1 WEEK 60 % ER IN CYCLIC PERIODS) GROUPS AT 10 WEEKS OF AGE UNTIL 82 WEEKS OF AGE. THE METHYLATION LEVELS OF ADIPOR1 IN THE CER GROUP WERE HIGHER THAN THOSE IN THE AL GROUP AT WEEK 49/50 (P < 0.05), WHILE THE LEVELS OF METHYLATION FOR ADIPOR1 AND LEPROT GENES WERE SIMILAR AMONG THE OTHER GROUPS. ALSO, THE METHYLATION LEVELS AT CPG2 AND CPG3 REGIONS OF THE PROMOTER REGION OF THE ADIPOR1 GENE IN THE CER GROUP WERE THREE TIMES HIGHER (P < 0.05), WHILE CPG1 ISLAND OF LEPROT METHYLATION WAS SIGNIFICANTLY LOWER COMPARED WITH THE OTHER GROUPS (P < 0.05). ADIPONECTIN AND LEPTIN GENE EXPRESSION LEVELS WERE CONSISTENT WITH THE METHYLATION LEVELS. WE ALSO OBSERVED A CHANGE WITH AGEING IN METHYLATION LEVELS OF THESE GENES. THESE RESULTS INDICATE THAT DIFFERENT TYPES OF ER MODIFY METHYLATION LEVELS OF ADIPOR1 AND LEPROT IN DIFFERENT WAYS AND CER HAD A MORE SIGNIFICANT EFFECT ON METHYLATION LEVELS OF BOTH GENES. EPIGENETIC REGULATION OF THESE GENES MAY PLAY IMPORTANT ROLES IN THE PREVENTIVE EFFECTS OF ER AGAINST MT DEVELOPMENT AND AGEING PROCESSES. 2021